Project 7: Structure and kinetic mechanism of neurotransmitter transporters

The available high-resolution structures of transporters from neurotransmitter transporters in multiple conformations allow for qualitative assessment of the principles of alternating access, but quantitative mechanistic understanding of coupling is far from complete. Knowledge of the kinetics of the transport reaction, which determines the order of binding of substrate and co-transported ion(s), and the sequence in which all relevant states are visited by the transporter, will help to reveal the coupling mechanism. In this research project, we will lay out the kinetic schemes by combining mathematical models with data from classical enzymatic methods. Mutagenesis, single particle cryo-EM, time-resolved crystallography, single molecule FRET methods and EPR will be used to complement the enzymatic approach. In this project the PhD student will

• test potential kinetic schemes using transport and binding assays
• experimentally manipulate the energy-coupling mechanism using mutations
• solve structures of relevant conformational states of mutants with altered coupling properties